The invention relates to an electronic-hydraulic control device for transmissions of vehicles, preferably, of motor vehicles.
In the control device disclosed in U.S. Pat. No. 5,709,134 to Ulm, only electrical and electronic components, but no mechanical or hydraulic control elements, are integrated in the control device. The mechanical or hydraulic control elements are situated in a valve block, which is installed in the automatic transmission of a motor vehicle. The control device is fitted onto valve domes of the valve block in which armatures actuated by the solenoid valves are located.
U.S. Pat. No. 5,749,060 to Graf et al. relates to a control device for an automatic transmission with solenoid valves, which is likewise placed onto valve domes of a valve block. The valve domes project through the transmission casing and into the casing of the control device. The control device is located completely outside the transmission casing.
In an automated manual transmission, the control device is used to select the appropriate gate arm in an automated manual transmission and to engage the desired gear in the selected gate arm. The gear selector provided for such a purpose is flanged onto the transmission. The hydraulic and mechanical actuating elements of the gear selector are located outside the transmission casing. To carry out a gear change, the corresponding gearshift shaft of the transmission is shifted from the outside. An external pressure supply is provided for the gear selector. The gear selector is connected for pressure supply purposes through hydraulic lines. The control lines are correspondingly long. There is a large number of contact points, for example, plug-in or soldered connections, which leads to a high probability of failure or to a high potential for the control device to fail. Because the hydraulic components are located outside the transmission casing, complex measures are required to prevent leakage and to protect against damage to components, which are acted on by pressure, for example, a crash protection for oil tanks.
Furthermore, a complex sealing configuration is required. High-strength, heavy connecting lines are required to connect the individual components of the control device. Partly because of the long line distances, they are susceptible to faults and require expensive measures to shield against radio interference. Because the control device includes a large number of components, it can only be produced and assembled at high cost. Moreover, the large number of components makes the control device heavy. Optimum utilization of space is impossible because of the large number of components.
It is accordingly an object of the invention to provide an electronic-hydraulic control device for transmissions of vehicles, preferably of motor vehicles, that overcomes the hereinafore-mentioned disadvantages of the heretofore-known devices of this general type and that, with a structurally simple and compact configuration, has a long service life, can be assembled without problems, and has only a low susceptibility to faults. Preferably, the vehicle transmission is a motor vehicle transmission.
With the foregoing and other objects in view, there is provided, in accordance with the invention, an electronic-hydraulic control device for a vehicle transmission having a transmission casing with an installation opening, solenoid valves with magnet parts and hydraulic parts, electronics for controlling the solenoid valves, and a pressure medium, the control device including a casing having a magnet casing part accommodating the electronics and the magnet parts of the solenoid valves, and a hydraulics casing part to be disposed at least partially within the transmission casing, to be supplied with the pressure medium, accommodating the hydraulic parts of the solenoid valves, and to be installed in the installation opening of the transmission casing. Alternatively, the hydraulics casing part is disposed at least partially within the transmission casing, is supplied with the pressure medium, and is installed in the installation opening of the transmission casing.
In the control device according to the invention, the magnetic parts of the solenoid valves are located in the magnet casing part, which is located outside the transmission casing. The electronics of the control device are also located outside the transmission casing in the magnet casing part. Consequently, there are only minor thermal loads acting on these sensitive components of the control device. Thus, the control device according to the invention operates reliably. The hydraulic parts of the solenoid valves are accommodated in the hydraulics casing part, which is located at least partially inside the transmission casing. Consequently, any leakage that occurs can flow directly into the transmission casing. As such, the need for complex seals is eliminated.
In accordance with another feature of the invention, the vehicle transmission has a pump with a motor for pumping the pressure medium and the hydraulics casing part has a shoulder to be attached to or is attached to the pump and the motor.
In accordance with a further feature of the invention, the shoulder has opposite sides and the pump and the motor are to be attached to or are attached to respective ones of the opposite sides.
In accordance with an added feature of the invention, the pump is disposed within the transmission casing.
In accordance with an additional feature of the invention, the motor projects out of the transmission casing.
In accordance with yet another feature of the invention, the vehicle transmission has a reservoir for holding the pressure medium.
In accordance with yet a further feature of the invention, the reservoir is integrated in the control device or in the casing or is accommodated within the hydraulics casing part.
In accordance with yet an added feature of the invention, the casing or the hydraulics casing part defines a receiving space, the reservoir has a bellows element, and the bellows element is accommodated within the receiving space.
In accordance with yet an additional feature of the invention, the bellows element is filled with air.
In accordance with again another feature of the invention, the reservoir has a piston for prestressing or pressurizing the pressure medium.
In accordance with again a further feature of the invention, the transmission casing has a spring and the spring imparts a force upon the piston.
In accordance with again an added feature of the invention, a plug connector is to be connected to or is connected to the motor.
In accordance with again an additional feature of the invention, the plug connector is to be disposed or is disposed inside the transmission casing.
In accordance with still another feature of the invention, a gear selector is disposed within the hydraulics casing part.
In accordance with still a further feature of the invention, the gear selector is to be actuated or is actuated by at least one of the solenoid valves.
In accordance with still an added feature of the invention, the vehicle transmission has shifting sleeves and the control device is to be used to hydraulically activate the shifting sleeves.
In accordance with still an additional feature of the invention, the shifting sleeves each have two pressure chambers and a pressure line is connected to each of the two pressure chambers.
In accordance with another feature of the invention, the vehicle transmission has transmission shafts and the pressure line is a bore in a respective one of the transmission shafts.
In accordance with a further feature of the invention, the vehicle transmission has pistons each accommodated within a respective one of the pressure chambers.
In accordance with an added feature of the invention, the pistons are identically configured and are disposed mirror-symmetrically with respect to one another.
In accordance with an additional feature of the invention, a mating stop is disposed in each of the shifting sleeves and the pistons are each assigned the mating stop for defining a limit position.
In accordance with yet another feature of the invention, the vehicle transmission has hydraulically displaceable gearshift shafts.
In accordance with yet a further feature of the invention, one of the pistons is positioned on each of the gearshift shafts.
In accordance with yet an added feature of the invention, the piston separates a pressure chamber into two partial pressure chambers each separated from one another.
In accordance with yet an additional feature of the invention, a pressure line opens into each of the two partial pressure chambers.
In accordance with again another feature of the invention, a stop is assigned to each of the pistons of the gearshift shafts.
In accordance with again a further feature of the invention, the stop is a piston to be acted on by pressure.
In accordance with again an added feature of the invention, the stop is to be displaced into a stop position under action of pressure.
In accordance with again an additional feature of the invention, the stop has piston surfaces and one of the piston surfaces remote from the gearshift shaft is larger than an opposite one of the piston surfaces.
In accordance with still another feature of the invention, at least one pressure line opens into the pressure chamber accommodating the stop.
In accordance with still a further feature of the invention, the vehicle transmission includes a gearshift fork for each of the gearshift shafts and each of the gearshift shafts is coupled, through a respective gearshift fork, to the shifting sleeves of the corresponding transmission shafts.
In accordance with still an added feature of the invention, the vehicle transmission includes actuators, gate arms, and gears and each of the gearshift shafts is to be rotated about an axis by one of the actuators to select one of a gate arm and a gear.
In accordance with still an additional feature of the invention, each of the actuators has an outer rotary piston and an inner rotary piston and the outer and inner rotary pistons rotate to a given extent with respect to one another.
In accordance with another feature of the invention, each of the gearshift shafts is connected in a rotationally fixed manner to the inner rotary piston.
In accordance with a further feature of the invention, each of the gearshift shafts is axially displaceable with respect to the inner rotary piston.
In accordance with an added feature of the invention, the vehicle transmission includes actuating devices each having a gearshift element and a rotary actuator and each of the gearshift shafts is to be coupled to a respective gearshift element.
In accordance with an additional feature of the invention, the actuating devices each have a shaft bearing the respective gearshift element and rotating with the respective rotary actuator.
In accordance with yet another feature of the invention, the hydraulics casing part is attached to the transmission casing.
In accordance with yet a further feature of the invention, the magnet casing part is formed of a nonconductive material.
In accordance with yet an added feature of the invention, a metal cover is connected to the casing.
In accordance with yet an additional feature of the invention, an electronics panel is attached to the cover.
In accordance with again another feature of the invention, a displacement sensor configuration is disposed within the magnet casing part.
In accordance with a concomitant feature of the invention, a pressure sensor configuration is disposed within the magnet casing part.
Other features that are considered as characteristic for the invention are set forth in the appended claims.
Although the invention is illustrated and described herein as embodied in an electronic-hydraulic control device for transmissions of vehicles, preferably of motor vehicles, it is, nevertheless, not intended to be limited to the details shown because various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.
The construction and method of operation of the invention, however, together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings.